Research On Interpolating Element-Free Galerkin Scaled Boundary Method For Viscoelastic Fracture Problems

Because of time effects and discontinuous problems,it is difficult to solve viscoelastic displacement and stress fields for the viscoelastic fracture.Therefore,it is necessary to study algorithms with high efficiency and precision.Based on the Interpolating Element-Free Galerkin Scaled Boundary Method(IEFG-SBM)and the temporally piecewise adaptive algorithm,the different time steps of viscoelastic relaxation and creep and the numerical solution under different stress types be analyzed in this paper,and more attention be paid for the accuracy of the calculation model.The advantages of numerical methods for solving viscoelastic fracture problems are mainly reflected in the discrete aspects of time domain and space domain.In the time domain discreteness,using the temporally piecewise adaptive algorithm expansion technique,it is only to calculate an instantaneous large elastic deformation problem at the initial moment by an iteratively solve way,and iterative calculations are not required in other periods.What's more,the calculation accuracy can be controlled by expansion order.In terms of spatial dispersion,IEFG-SBM only needs to discretize the nodes on the boundary of the calculation domain,which reduces the solution dimension of the problem.At the same time,the use of improved interpolating moving leastsquares(IIMLS)to construct shape functions has interpolation properties,which facilitates the implementation of numerical algorithms.In order to play the above advantages,programs related to viscoelastic stress relaxation and displacement creep analysis were compiled by using MATLAB language,and the influence of the unsynchronized length and the accuracy of node layout were analyzed.Comparison with ABAQUS calculation results,it shows that the numerical algorithm in this paper is more effective and accurate.